A conventional wire rope flaw detector includes an exciting core having at least two magnetic poles and closely facing a wire rope, an excitation permanent magnet embedded in the exciting core, and a detection coil disposed between those two magnetic poles (for example, refer to Patent Document 1). The conventional wire rope flaw detector magnetically saturates the wire rope by the two magnetic poles to generate a leakage magnetic flux from a damaged portion such as disconnection of a wire, and detects the leakage magnetic flux by the detection coil, to thereby detect the damaged portion of the wire rope.
Further, there is another example in which an electromagnet is used to excite the wire rope to provide AC excitation (for example, refer to Patent Document 2).
Patent Document 1: JP 09-210968 A
Patent Document 2: JP 11-230945 A